Electric furnace.



J. W. BROWN. ELECTRIC FURNACE.

APPLIOATIQN FILED MAR.5;1910,

Patented Mar. 28', 1911.

Jfu. venfor APPLICATION FILED MAB. 5, 1810.

J. W. BROWN.

ELECTRIC FURNACE.

Patented Mar.28,'1 911.

' To all it may mm.-

- citizen of the United 'States, .res i ding at. Lakewood, in the countyof Cuyalio gfaand' naces, ofwhich t "UN TED STATES PATENT OFFICE.

JOHN BIBOWN, OF LAKEWOOD, OHIO, ASSIGNOR TO NATIONAL CARBON'GOFEPANY, A CORPORATION OF NEW JERSEY.

'- nnno'rnrc FURNACE.

Application filed March 5', 191a. Serial no. 547,406.

Be it known that 'IQJoHN BRowN, a

State of Ohio, have invented a certaiitnew and useful Improvement in ElectricYFun he following is a full, clear, and exact description. i r

The present invention relates to electric furnaces Without regard to' the specific means employedf'or generating the heat from the electric current.

The object of the invention has been to devise an arrangement of sections or series of compartments to'produce a ring type of electric furnace with a systemv of-a-ir orgas circulation having advantages in the matters of efiiciency and ease and flexibility ofoperation not hitherto attained.

It has been a further object todevise a furnace of this character in which gaseous fuel can be, used in conjunction with the electr c heat, with systems of gas or air circulation in cases where it is desirable to se cure certain eifects;

The above. objects and desirable advan .tages it will be seen are attained that embodiment of my invention described in the following specification and illustrated in the accompanying drawings, in Which- Figure 1 is a top plan somewhat diagrammatic in character and partly in section following the crooked dotted line 1--1 on Fig.

2 ofan electric furnace constructed in accordance with my invention. Fig. 2 is a side elevation of said furnace partly in vertical section following the crooked. dotted line marked 2-3-4-5 on Fig. 1. Fig 3 V is an enlarged vertical section through. the

wall betweentwo adjacent furnace compartments, the section being in the plane indicat'ed by line 2-2' on Fig. 1. Fig, 4 is' a similar section in the plane indicated by line 3-3 on Fig. 1. Fig. 5 is a similar section .in the plane indicated by line l4 on" Fig. 1. Fig. 6 is a'transverse vertical 'sccvtion inthe plane indicated by line 6-6 on Theif'urnace as an entirety is comprised of a series of sections L, L, L etc, arranged to sons to form two rows of three in a row,

which rows are separated by the longitur- Specification of Letters Patent.

Patented Mar, 23,1911.

dinal wall =-M,-and two end sections;- The several siactions are additionally separated from each other by vertical transversely eX- tended walls'Nin which are various fiues controlled by valves, by-means of which corresponding parts of different sections may be put into communication with each other or. with the gas or air supplies.

-Each furnacefsection includes a closed heatin chamber A, in which are placed the articles B to be heated,' together with suitable resistance material in; which said articles are embodied. More or less coin pletely enveloping this heating chamber, in

each section, are passageways for gases, such 7 0 enveloping passageways being so construct ed, disposed and controlled as tobe capable of utilization for the passage therethrough of gases which shall either be burned therein to produce heat, or, if not burned, to act as heat insulation to prevent or reduce the radiation of heat from the heating chamber walls,.or to take up heat from certain'sections and transfer and giveup, this heat to the charge in other sections. Iii arranging these passageways, I prefer to provide one passageway C, containing checker-Work c, beneath the heating chamber- A which' checker Work will permit the passage of the gaseous fluid and will also support the heating chamber and the charge therein.

It is also preferred that there should be a conduit C' above the heating chamber inwhich there should be no checker work, or

in which the checker work should be of teinporary character and easily removable togetherwiththe top of said chamber, so that one can conveniently withdraw the charge through the top of the section after the heating operation has been completed. It-furtlier may. be desired to have the passage ways c containing checker work at both sides of the chamber A.

Beneath the middle longitudinal wall M of the furnace is a discharge conduit P adapted to be connected with the stackfor Beneath the the escape of the spent gases. front and rearlongitud nal-=walls are the mains E, E, for the admission of an"; and

underneath the transverse separating walls N are branch mains E connecting the inlet mains E with the discharge main P, there being in these branch mains a valve 6 (indicatedconventionally in' Fig. 1), by which they may be severally placed in comniunication either with the inlet mains or the outlet inains as desired. Longltudlnally extended "gas mains F are also formed in the foundaor with both the air and mains, or both.

sections and the corresponding parts thereof may be placed in communication with each other.

The vertical fiues G, G in wall N com- I municate, through horizontal fines g, g, with the heating chambers A in the two adjacent furiiacesections. At their lower ends each pair-of these fines G, G converge and are merged together to form a flue G and each of these flucs G is connected with an air branch E, there being a valve to control the flow of gas from said branch to said flue. Each of the fiucs G is also connected through a horizontal flue f with one of the branch gas mains F, there being a valve f in the flue f". A valve G is hung from the lower end of that part of wall N which separates flues G and G, whereby if it hangs vertically the two fiues' are in communication. If this valve be swung in one direction or the other it will shut off the communication between either flue G, G and the flue G In this same bridge wall N and above the flues G, G are horizontal fines T which establish communication between two adjacent conduits C, C; anda sliding valve 25 is, provided through which, by the 'dropping ofthe valve this communication may be discontinued or by raising'it, it may be opened up.

In the same bridge wall N are other verticalfines D, D communicating through fines d, d with the two passageways C C in adjacent sections. At their lower ends these flues D, D converge and are merged to form the tines D and these fines communicate with the air branches E, there being valves e to control the 130w of air from the branches into the fines D Horizontal valves f containing valves 7' are' provided through which gas may flow from the branch'gas mains F into the fines D A valve D is provided inorder that the flues D, D may he placed in communication with each other or either of them placed in communication with the air and gas mains.

In the same bridge Wall N are vertical fines H, H which communicate through a plurality of horizontal fines h, h with the compartments (1, C containing checker work at the sides of the two adjacent fur crating means will project so that a workman in these various tunnels can control the position of the valves. There is also around the entire right of furnace sections an inclosed passageway-V into wh! h'other valve operating means will project. Each furnace section L has anindependent cover K removable for charging and uncharging that section. I

It is to be understood that this invention, broadly considered, is not restricted to the particular construction and arrangement of lines, mains and valves. Any other arrangement of such. parts may be adopted which will permit the admission of gas and air to any section or sections, and front one section and its quired.

In each-heating chamber, and at the ends thereof isan electrode S,-which are to be connected with the conductors I, I, according as any heating chamber isto be electrically heated.

parts to another section, as re- In the operation of the furnace I propose heating the several compartments and the charges therein successively, thus advancing the heat treatment through the ring after the general manner of gas fire ring furnaces previously well known. It is my purpose to use the flow of gases from unit to unit in cooperation or in conjunction with the electric heating so as to secure the most desirable effects. Inasmuch as the operation in its broader'aspect contemplates the use of a current of air or other non-combustible gas or gases as well as combustible gases, I have used the expression gaseous fluids as referring to all such gases, and I would have the. phrase so construed-in the specification and claims, except where the phrase is specifically qualified. Owing to the systenrof conduits and controls which I have arranged, it will be seen that it is possible to use the furnace to advantage with electric current as the sole source of heat, or with the effects of electric heating combined with that of, combustion heating,

Contemplating first the use of the furnace with the electric current as the sole source of heat, in which heat insulation and transference is effected by means of currents of air or other gases more or less completely enveloping the charge in each compartment, it may be assumed that the charge in section Lhas been baked and is'sufiiciently cool to be removed; that the charge in sections "not only nant condition in order to avoid L -and L have received their full bake, and are in the process of cooling, and section L is being subjected to the highest heat necessary to 'eifect the desired baking. Under these circumstances air or other 'nonecombustiblc gas, should any such be obtainable, may beadmitted through the vertical lines D, G and-H of sections L so as to flow through the'conduits-C', O, G 'env'eloping the heating chamber, and through said heating chamber, and be forced or drawn forward through the ports or passageways described in the conduits C, C, C of section L from which they pass through the ports described into corresponding parts of section L By this means the previously baked charges in sections or units L and L will become more rapidly cooled than would otherwise be the case and the gases passing into thesection L will have been raised to a very high temperature, so that they serve as ainetli'ective insulating medium in passing tltroug'll the c'ol'iduits C, C of the unit L which is being subjdctcd to the full heat of the electric yurrent.- By a similar arrangement of the valves the gases which have passed through the envelii'ping con diiits of the section L are led through each successive compartment in the entire ring up to the last compartment charged. The gases passing into the furnace of course go 1n at ordinary temperatures, but in their progress up to-the unit subjected to thjeie tric heat they reach a hi her temperatiirein' each suecessive unit at the expense of the heat contents 'of the walls and. charges of the units through which they pass. In passing throughthe unit under the electric tiring, it will be seen that the enveloping gases tend to prevent radiation of heat electrically generated in the charge,but they willgive up a portion of their heat to the charge, at least in the initial stages of the electric heating, and as they pass from this unit at a very high temperature through the units charged and prepared for baking, they will transfer the heat toi'the Walls of the, units and the charge's' bontained therein until the outlet is i-reache ,Th efiiect and advantage 'of sucha n ope "n will be; plain. It is to be noted-in pra tical operation that a pointwill be .reache. in the electric baking at which the charge'will be come heated to a temperature higher than" that of the enveloping gases, and from this point on to'the end of the bake the flow of the envelopin'ggases should be diminished, maintaining them in a substantially stagcarrylng away the heat radiated from the charge, and thus increasing the rate of radiation losses.' When the full electric bake has been given and the current transferred to the nextsucf effec s;

seeding section the flow of air or gases through the urnace may be again instituted and the process repeated-as described. It Wlll be clear, ofcourse, that with such 'an arrangement there is, a Wide range of possibility in choosing such gases to pass through,

the furnace as Will produce certain desired chemical or physical efl'ects. In such a case the gases might flow through the heating v to the flue'baking heat are in such communi- '80 previously subjected cation that the incoming gases'fiow through them cooling ofi' the charge and transferring the heat of. the unit under treatment to thoseunits succeeding it. The air or gas, or both, when both are admitted concurrently,,are brought in under suitable conditi'ons'to prevent combustion until the proper point is rem'hml. Under these condit-ions'the'gases act heat collectors prior to their entrance into section in this section after the internal tempera- L wherein. the are burned and ture of the charge exceeds that of the gases the latter act as heat insulators. hen the temperature around the charge in section L exceeds that around the charge insec tion L ,'firing by coinbustion-- in section L may be advantageous in order to preventheat radiationfrom section L back'to L Likewise it may be desirableto start combustion in section L as soonjas the electric firing is commenced in section L also for the purpose of preventing radiation from;

section L during the electric firing period Of course the furnace iscapable of being handled in other manners for securing other but the above clearly illustratest e flexibility of operationb'f whichthis furnace is capable, and by which a greater etlic'iency is obtained than has" been'possibl'e in, any electric furnace hereto-fore known ,to} me.

()wingto the fact that there are many H ndi-- tion, I. desire that it should be clearly unan example illustrative in its characters.

,fications of the des cribed method of opera- 'derstood that the method described is merely As a resume of the advantages ofthe fur-, nace I would call attention to the 'factthat when non-combustiblegases-aroused as described in the fir 't partof-the; specification,

it 'willIbe possible peratu'res with I cutting down of rad ation losses and .to ,sav-

to obtain the highest tem- .ing' of the energy required to heat the walls andthe charge up to the point whereelectric' heating becomes eflicient. Further. it "will be quite easy in: this operation to'recoVer by-- products and to heat'th'echarge in any desired atmosphere, and to; maintain the;

great economy owing to the charge in the compartment under treatment at a uniform temperature throughout the compartment and to attain the temperature in all of the compartments successively.

In the case where combustible gases are used for the purpose of combined combustion heating with electric heating, it will be seen that the highest temperatures may be.

obtained with maximum efficiency both in respectto fuel and electricity due to the greater temperature obtainable by combustion of gasesheated to a high temperature being burned, and to the use of the fuel at a low ten'iperature and the electric heating,

together with the fuel at a high tempera ture. as well as to amaximum decrease" in radiation losses of electric heating.

Having described my invention, I claim: 1. An electric furnace of the ring type having a series of sections or units containing independent electric heating means, gaseous fluid conduits being provided in certain of the walls of said sections, the walls between :uljacent sections being provided with fines leading to said conduits, a gaseous fluid main with which said fines are con tween the said mainand either set of fines,

or both sets of fines, and means for shutting off the main from the fiues.

3. An electric furnace of the ring type comprising a series of sections or units, each section being provided w th a heating chan1-- her at least partially enveloped by conduits controlling the connection between the main and the fines;

4. An electric f'urnace of the ring type having a series of sections or units con taining independent electric heatiin; means, gaseous fluid conduits being provided in certain of the walls of said sections, the walls with separate sets of fines one for each section, sa1d fines merging into a con'nnon chamber at onev end, a gaseous fluid main ;ed to separate either of said fines. from said chamber, and another valve for shutting off the said main from the chamber. y

5. An 'elcctricfiu'naec of. the 'rhig; type having a series of sections or units containing ilnlependent electric heating means, gaseous fluid 'conduits being provided in certain of the walls of said sections, the walls between adjacent sections being provided with separate sets of fines, one for each section, a gas main, an air Ina-in con nected with the said fines, and means for shutting off theflues from either or both of the said mains.

.In testimony whereof, I hereunto aflix my signature in the presence of two witnesses. y JOHN W. BROWN.

iVit-nesses' E. L. T

for conducting the gaseous fluid,'the walls between adjacent sections being provided connected with said chamber, a valve adapt 

